OTR-8100

OTR-8100 (also known as BR1733) is an orally bioavailable small molecule proteolysis-targeting chimera (PROTAC) designed to degrade the androgen receptor (AR). Developed by Shanghai Aolu Biomedical Technology, it is currently being evaluated in Phase Ib/II clinical trials for the treatment of metastatic castration-resistant prostate cancer (mCRPC). The drug is specifically targeted at patients who have progressed after treatment with at least one androgen receptor pathway inhibitor (ARPI) and prior chemotherapy. By inducing the ubiquitination and subsequent proteasomal degradation of the AR protein, OTR-8100 aims to overcome common resistance mechanisms in prostate cancer, such as AR mutations, amplifications, and splice variants, which often limit the efficacy of traditional AR antagonists.